Weiss Instruments WEISS-LF441-100-4L Pressure Gauge 0-100 Psi

Product Description

The Weiss Instruments WEISS-LF441-100-4L is a 4-inch liquid-filled pressure gauge rated for 0-100 psi service. The bourdon tube movement is dampened by glycerine fill, which reduces pointer flutter and protects internal components in high-vibration or pulsating-pressure applications. The case is Type 304 stainless steel with a crimped, polished stainless ring and a clear acrylic window. Accuracy is plus or minus 1.0% of full scale, meeting ASME B40.100 Grade 1A. The dual-scale dial reads in both psi and kPa. HVAC technicians, plumbers, and pipefitters install this gauge on pressurized systems where reliable, steady readings are critical.

This gauge is suited for residential and light commercial HVAC, hydronic heating, plumbing, and general industrial piping applications. The 1/4-inch NPT lower connection fits standard gauge ports on pumps, boilers, chillers, pressure vessels, and test manifolds. The glycerine-filled design handles process and ambient temperatures from -40 degrees F to 140 degrees F, making it appropriate for both indoor mechanical room installations and moderate outdoor service environments.

Key Features

• Glycerine-filled case dampens vibration and pulsation to stabilize pointer readings
• Type 304 stainless steel case and crimped stainless ring for corrosion resistance
• ASME B40.100 Grade 1A accuracy at plus or minus 1.0% full scale
• Dual psi and kPa scale on white aluminum dial with black and red markings
• 1/4-inch NPT lower connection with brass socket and threaded restrictor
• Phosphor bronze bourdon tube with brass rotary movement and bushings

Compatibility

Designed as an OEM-style or field-replacement liquid-filled pressure gauge for residential and commercial HVAC, hydronic, plumbing, and general industrial piping systems requiring a 4-inch dial and 1/4-inch NPT lower connection rated to 100 psi.

Installation Notes

A licensed plumber or HVAC technician should install this gauge in accordance with applicable local codes and ASME B40.100 guidelines. Isolate and depressurize the system before removing any existing gauge or fitting. Apply thread sealant appropriate for the process fluid to the NPT threads and tighten with a wrench on the hex of the socket, not on the case or ring. Do not exceed the rated pressure range, as overpressure will damage the bourdon tube and void calibration.

Technical Specifications

• Pressure Range: 0-100 psi (0-700 kPa)
• Dial Size: 4 inches
• Connection: 1/4 NPT Lower
• Accuracy: plus or minus 1.0% Full Scale, ASME B40.100 Grade 1A
• Fill Fluid: Glycerine
• Case Material: Type 304 Stainless Steel
• Ring: Crimped, Polished Stainless Steel
• Window: Clear Acrylic
• Bourdon Tube Material: Phosphor Bronze
• Socket Material: Brass with Threaded Restrictor
• Movement: Brass Rotary with Bushings
• Pointer: Black Anodized Aluminum
• Dial: White Aluminum, Black and Red Markings
• Process Temperature Range: -40 degrees F to 140 degrees F (-40 degrees C to 60 degrees C)
• Ambient Temperature Range: -40 degrees F to 140 degrees F (-40 degrees C to 60 degrees C)

Standard Information

• Brand: Weiss Instruments
• Manufacturer Part Number: WEISS-LF441-100-4L